Terminating a program

[frank9815]

So im writing a program for the quadratic formula, and have everything except for something that will terminate the program if a letter is entered into a, b, or c as a value. what is the best way to do so?

[Athar]

The program terminates when you return from the main function.

[frank9815]

guess i asked the wrong question, i meant that when the program prompts the user for a integer value and the user types in a letter, i would like it to come up with Improper value input and then terminate the program. currently if you put in a letter it goes crazy and shows some strange output values.

[Duthomhas]

You need input validation (to the rescue!)...
http://www.cplusplus.com/forum/beginner/18258/#msg92955
http://www.cplusplus.com/forum/beginner/13044/#msg62827
(Variations on a theme. The second way is the most robust way.)

Hope this helps.